DN05019/D
Design Note – DN05019/D
200V Boost Regulator
Device
Application
Input
Voltage
Output
Voltage
Output
Current
CS5171
General
12V
200V
20mA
Topology
Enhanced
Boost
Key Features
Circuit Description
The following solution is presented to
support a low voltage to high voltage DC to
DC boost application. The module has an
input voltage range from 3.3V to 30V. The
module provides 1 regulated output of 200V
but can be configured for different outputs.
The CS5171 is a 280 kHz/ switching
regulators with a high efficiency, 1.5 A
integrated switch. The part operates over a
wide input voltage range, from 2.7 V to 30 V.
The flexibility of the design allows the chip to
operate in most power supply configurations,
including boost, flyback, forward, inverting,
and SEPIC. The ICs utilize current mode
architecture, which allows excellent load and
line regulation, as well as a practical means
for limiting current. Combining high frequency
operation with a highly integrated regulator
circuit results in an extremely compact power
supply solution. The circuit design includes
provisions for features such as frequency
synchronization, shutdown, and feedback
controls for either positive or negative voltage
regulation.
 Wide Input Range: 2.7V to 30V
 High Frequency Allows for Small
Components
 Minimum External Components
 Easy External Synchronization
 Built-in Overcurrent Protection
 Frequency Foldback
 Thermal Shutdown with Hysteresis
 Integrated Power Switch: 1.5A Guaranteed
Figure 1: CS5171 Demonstration Board
Rev 0 - September, 2011
DN05019/D
Figure 2: CS5171 Pinout
Table 1: Pin Description
PIN
PIN NAME
1
VC
2
3
4
5
6
7
8
DESCRIPTION
Loop compensation pin. The VC pin is the output of the error amplifier and is used for loop compensation,
current limit and soft start. Loop compensation can be implemented by a simple RC network as shown in the
application diagram on page 2 as R1 and C1.
FB
Positive regulator feedback pin. This pin senses a positive output voltage and is referenced to 1.276 V. When
the voltage at this pin falls below 0.4 V, chip switching frequency reduces to 20% of the nominal frequency.
Test
These pins are connected to internal test logic and should either be left floating or tied to ground. Connection
to a voltage between 2 V and 6 V shuts down the internal oscillator and leaves the power switch running.
SS
VCC
Synchronization and shutdown pin. This pin may be used to synchronize the part to nearly twice the base
frequency. A TTL low will shut the part down and put it into low current mode. If synchronization is not used,
this pin should be either tied high or left floating for normal operation.
Input power supply pin. This pin supplies power to the part and should have a bypass capacitor connected to
AGND.
AGND
Analog ground. This pin provides a clean ground for the controller circuitry and should not be in the path of
large currents. The output voltage sensing resistors should be connected to this ground pin. This pin is
connected to the IC substrate.
PGND
Power ground. This pin is the ground connection for the emitter of the power switching transistor. Connection
to a good ground plane is essential.
VSW
High current switch pin. This pin connects internally to the collector of the power switch. The open voltage
across the power switch can be as high as 40 V. To minimize radiation, use a trace as short as practical.
Rev 0 - September, 2011
DN05019/D
Figure 3: CS5171 Block Diagram
Rev 0 - September, 2011
DN05019/D
Performance Information
The following figures show typical performance of the evaluation board.
Efficiency (%)
CS5171 Efficiency
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
0
3
6
9
12
15
18
21
18
21
Output Current (mA)
Figure 4: CS5171 12V to 200V Efficiency
Load Regulation
202.00
Output Voltage (V)
200.00
198.00
196.00
194.00
192.00
190.00
188.00
186.00
0
3
6
9
12
15
Output Current (mA)
Figure 5: CS5171 12V to 200V Load Regulation
Rev 0 - September, 2011
DN05019/D
Schematic
Figure 6: CS5171 12V to 200V Schematic
Rev 0 - September, 2011
DN05019/D
Table 2: BOM for the CS5171 200V Design
Reference
C1 C3-4
C6 C10
Qty
Description
Value
C12
CC
Tolerance
Footprint
Manufacturer
Manufacturer Part Number
5
SMT Ceramic Capacitor
NI
20%
1
SMT Ceramic Capacitor
1u
±10%
603
Taiyo Yuden
GMK107BJ105KA-T
1
SMT Ceramic Capacitor COG
NI
±5%
603
AVX
C1608C0G1E682J
CP
1
SMT Ceramic Capacitor
100n
±5%
603
Murata
GRM188R71C104JA01J
CP1
1
SMT Ceramic Capacitor
2.2uF
±10%
603
TDK Corporation
C1608X5R1A225M
C2
1
10uF
±20%
1210
Taiyo Yuden
GMK325F106ZH-T
U1
1
SMT Ceramic Capacitor
500 kHz Synchronous Swiitching
Regulator
500 kHz
NA
SOIC8
ON Semiconductor
CS5171/CS5173
D1-5 D8
6
Standard Rectifier
100V 1A
NA
SOD-123-2
ON Semiconductor
MMSD4148
D7 D6
2
Standard Rectifier
30V 10mA
NA
SOD-123-2
ON Semiconductor
BAT54T1G
LOUT
1
SMT Inductor
33uH
20%
(12.3 x 12.3 x 8.1)mm
Wurth
744771133
Q1
1
N-Channel Power Mosfet
100V 55mOhm
NA
DPAK-4
ON Semiconductor
NTD6415AN
R1
1
SMT Resistor
162k
±1.0%
603
Vishay / Dale
CRCW0603162KFKEA
R2
1
SMT Resistor
3.16k
±1.0%
603
Vishay / Dale
CRCW06037K87FKEA
R3-4
2
SMT Resistor
165k
±1.0%
603
Vishay / Dale
CRCW0603165KFKEA
R5-6
2
SMT Resistor
0
±5.0%
603
Vishay / Dale
CRCW06030000Z0EA
R7
1
SMT Resistor
100R
±5.0%
603
Vishay / Dale
CRCW0603100RJNEAHP
RC
1
SMT Resistor
NI
±1.0%
603
RC1
C5 C7-9
C11
1
SMT Resistor
4.99k
±1.0%
603
Vishay / Dale
CRCW06034K99FKEA
5
Aluminum Eectrolytic Capacitor
1uF 100V
±20%
TH
Panasonic - ECG
ECA-2AM010B
Rev 0 - September, 2011
DN05019/D
Figure9: Ripple Voltage 12 V to 200 V with no Load
Figure10: Output Ripple 12 V to 200 V with 10 mA Load
Figure10: Ripple Voltage 12 V to 200 V with 20 mA Load
Figure12: Transient Response no Load to full load
Rev 0 - September, 2011
DN05019/D
Figure12: Transient Response Full Load to No load
Figure14: CS5171 Soft Start with only compensation
Figure15: Full load Soft Start with 2.2uF Extender Circuit
Disclaimer: ON Semiconductor is providing this design note “AS IS” and does not assume any liability arising from its use; nor does ON Semiconductor convey any
license to its or any third party’s intellectual property rights. This document is provided only to assist customers in evaluation of the referenced circuit implementation and
the recipient assumes all liability and risk associated with its use, including, but not limited to, compliance with all regulatory standards. ON Semiconductor may change
any of its products at any time, without notice.
Design note created by Bryan McCoy, e-mail: Bryan.McCoy@onsemi.com
Rev 0 - September, 2011